Ozone processing device

ABSTRACT

An ozone processing device includes: a mounting base on which a substrate is mounted; a heating device to heat the substrate on the mounting base; a plurality of plates facing the substrate on the mounting base and equipped with discharge openings on the surface facing the substrate that discharge ozone gas in the direction of the substrate; and a gas supply device supplying ozone gas to the discharge openings of the plates to allow them to discharge gas. The plates are arranged in a co-planar manner with gaps formed between adjacent plates. The plates have a small volume so that even if there is heat transfer between the plates and the substrate, thermal equilibrium is achieved between the plates and the substrate in a short time, thus making temperature management of the substrate easy.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is a Continuation of International patentapplication Serial No. PCT/JP02/12469 filed Nov. 28, 2002, which waspublished in Japanese on Jul. 31, 2003 as WO 03/063222 A1, and JapanesePatent Application No. 2002-15919 filed Jan. 24, 2002 which isincorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to an ozone processing device whichdischarges a processing gas containing at least ozone onto the surfaceof a substrate such as a semiconductor substrate or a liquid crystalsubstrate in order to form or to improve an oxide film on the substratesurface or to remove a resist film formed on the substrate surface.

[0003]FIG. 7 and FIG. 8 show examples of conventional ozone processingdevices. FIG. 7 is a cross-section drawing showing a portion of an ozoneprocessing device based on a conventional technology and is across-section drawing along the E-E line in FIG. 8. FIG. 8 is abottom-view drawing along the D-D line in FIG. 7.

[0004] As FIG. 7 and FIG. 8 show, an ozone processing device 100 isequipped with: a mounting base 101 on which a substrate K is mounted; agas supply head 102 disposed above the mounting base 101 so that itfaces the substrate K. The mounting base 101 and the gas supply head 102are disposed in a chamber (not illustrated) equipped with a closedspace. The chamber (not illustrated) is formed with a suitable exhaustopening from which internal gasses are discharged to the outside.

[0005] The mounting base 101 is equipped with an internal heating device(not illustrated) formed from a heater. The substrate K mounted on theupper surface is heated by this heating device (not illustrated). Also,the mounting base 101 can be raised and lowered by a raising/loweringdevice (not illustrated).

[0006] The gas supply head 102 is formed from a nozzle module 103 and acooling module 104, both formed as block-shaped members that are stackedvertically and bonded. A cavity 105 is formed on the upper surface ofthe nozzle module 103, i.e., the surface where it bonds with the coolingmodule 104. Nozzles 106, which communicate with the cavity 105 and openon the lower surface, are arranged in a plurality of rows in a staggeredmanner. Exhaust grooves 107, which open on the side surfaces, are formedon the bottom surface between the rows of the nozzle 106.

[0007] The cooling module 104 is formed from an upper member 104 a and alower member 104 b, which are stacked vertically and bonded. A coolingfluid path 108 (108 a, 108 b) is formed on the bonding surface betweenthe upper member 104 a and the lower member 104 b in a zigzag patternextending from one side surface to the other side surface. The coolingfluid path 108 is connected by way of pipes 109, 110 to external coolingfluid supplying means 111. In this manner, the cooling fluid path 108,the pipes 109, 110, and cooling fluid supplying means 111 form acirculation path for cooling fluid to allow the cooling fluid tocirculate.

[0008] The cooling module 104 is formed with a through-hole 112 thatpasses from the upper surface to the lower surface and communicates withthe cavity 105. This through-hole 112 is connected by way of a pipe 114connected thereto to an external ozone gas generating device 113. Apredetermined concentration of ozone gas (processing gas) is suppliedfrom ozone gas generating means 113 by way of the pipe 114 and thethrough-hole 112 to the cavity 105, and is discharged toward thesubstrate K from the lower openings of the nozzle 106.

[0009] With the ozone processing device 100 described above, thesubstrate K is mounted on the mounting base 101. The substrate K ismounted on heating means (not shown) and the mounting base 101 is raisedby raising/lowering means (not shown) to a position, as shown in FIG. 7,where it is separated by a predetermined space from the gas supply head102.

[0010] Then, the ozone gas is supplied from ozone gas generating device113 to the cavity 105 by way of the pipe 114 and the through-hole 112,and this is blown toward the substrate K from the lower openings of thenozzles 106.

[0011] The ozone gas flows discharged from the nozzles 106 in thismanner run into the surface of the substrate K, flow along the surface,and run into each other to form a flow toward the discharge grooves 107.During this flow, the ozone (O₃) is heated by the substrate K. Thisheating and the contact with the substrate K and the resist cause thegas to break down into oxygen (O₂) and active oxygen (O*). This activeoxygen (O*) forms an oxide film on the surface of the substrate K,improves the oxide film on the surface of the substrate K, or removesthe resist film formed on the surface of the substrate K by athermochemical reaction with the active oxygen (O*).

[0012] Then, the ozone gas that flows into the discharge grooves 107after the processing it performs is discharged by way of the dischargegrooves 107 from between the substrate K and the gas supply head 102.

[0013] In this ozone processing device 100, the gas supply head 102 iscooled by a cooling fluid, and the ozone gas that flows through thethrough-hole 112, the cavity 105, and the nozzle 106 is cooled by thecooling fluid. Thus, the ozone gas flowing through the through-hole 112,the cavity 105, and the nozzle 106 is prevented from undergoing thermaldecomposition due to increased temperature, thus preventing the ozoneconcentration from dropping due to thermal decomposition.

[0014] Also, since the substrate K and the gas supply head 102 arebrought close to each other so that the lower openings of the nozzles106 can be near the substrate K, the ozone discharged from the nozzles106 is prevented from being thermally decomposed before it reaches thesubstrate K and a thinner layer of ozone gas flowing on the substrate Kis provided. This allows more ozone to contribute to the formation ofthe oxide film, the improvement of the oxide film, or the removal of theresist film.

[0015] In this conventional ozone processing device 100, the gas supplyhead 102 is positioned close to the substrate K as described above. Thiscauses heat to transfer from the substrate K and the mounting base 101to the gas supply head 102, resulting in an increase in temperature inthe gas supply head 102.

[0016] Because the volume (capacity) of the gas supply head 102 is highand is cooled with the cooling fluid described above, thermalequilibrium in the substrate K and the gas supply head 102 becomesdifficult to achieve and takes a long time. As a result, the temperatureof the substrate K does not stay constant over a long period of time,leading to unevenness in the ozone processing operation.

[0017] Also, the processing gas discharged from the nozzles 106 flowinto the discharge grooves 107. The processing gas discharged from thenozzles 106 toward the center of the nozzle module 103 is dischargedfrom the nozzles 106 disposed toward the ends because the gas dischargedfrom the nozzles 106 flow into the exhaust grooves 107. The gas flowinginto the exhaust grooves 107 obstructs the flow within the exhaustgrooves 107, making it difficult for the gas discharged from the nozzles106 toward the center from being discharged out between the substrate Kand the gas supply head 102.

OBJECTS AND SUMMARY OF THE INVENTION

[0018] The object of the present invention is to overcome the problemsdescribed above and to provide an ozone processing device that allowseasy management of the temperature of the substrate and that quicklydischarges the gas from the upper surface of the substrate after the gasfinishes performing ozone processing operations.

[0019] The present invention relates to an ozone processing deviceincluding a mounting base upon which a substrate is mounted, heatingdevice heating the substrate on the mounting base, a facing platedisposed facing the substrate on the mounting base and equipped with aplurality of discharge openings discharging a processing gas containingozone toward the substrate and a through-hole disposed between thedischarge openings and passing through the front and back surfaces, anda gas supplying device supplying and discharging the processing gas tothe discharge openings of the facing plate.

[0020] According to this invention, the processing gas containing ozoneis supplied by gas supplying device and is discharged toward thesubstrate from the discharge openings on the facing plate disposedfacing the substrate mounted on the mounting base. The substrate isheated by the heating device.

[0021] The processing gas discharged in this manner collides with thesubstrate, forming a flow along the substrate. In this flow, the ozone(O₃) is heated. This heating and the contact with the substrate K andthe resist causes it to break down into oxygen (O₂) and active oxygen(O*). This active oxygen (O*) results in the formation of oxide film onthe substrate surface or improvement in oxide film on the substratesurface or removal of resist film formed on the substrate surfacethrough thermochemical reaction.

[0022] The processing gas discharged from the discharge openings andflowing along the substrate then collides with each other to form a flowtoward the through-holes. This is then discharged toward the back sideof the facing plate through the through-holes, i.e., is discharged frombetween the substrate and the facing plate. As a result, the processinggas that has completed its processing operation does not remain abovethe substrate surface and the processing gas discharged from thedischarge openings can reach the substrate surface unobstructed. Thisallows effective processing such as the formation or improvement ofoxide film or removal of resist film.

[0023] The facing plate described above serves to control the thicknessof the processing gas flow along the substrate surface. From thisperspective, it would be preferable to have the facing plate disposed asclose as possible to the substrate. This allows a thin gas flow layerover the substrate surface and allows more ozone to contribute toforming or improving oxide film or removing resist film, thus improvingprocessing effectiveness.

[0024] When the facing plate is brought close to the substrate, however,thermal transfer from the substrate to the facing plate takes place. Ifthe volume is large, as in the gas supply head in the conventionaltechnology, thermal equilibrium between the two elements becomesdifficult and the temperature of the substrate does not stay constantover a long period of time, thus leading to unevenness in processing. Inthe facing plate according to the present invention, however, the volumeof the gas supply head is smaller than that of the conventional example,so this problem is corrected.

[0025] The through-holes are lined up to partition the facing plate intomultiple regions, and a discharge opening is formed in each regionpartitioned by the through-holes.

[0026] This allows the processing gas discharged from the dischargeopenings to be effectively discharged from between the substrate and thefacing plate. If the regions are partitioned so they are the same size(area), the substrate surface can be processed without unevenness. Thesize of the regions can be set to suit the required processing speed.

[0027] It would be preferable for the through-hole diameter to be atleast 0.5 mm and no more than 3 mm. If the hole diameter exceeds 3 mm,unprocessed sections corresponding to the through-holes can remain onthe substrate surface. If the diameter is less than 0.5 mm, thedischarge efficiency of the processing gas is very poor, and theprocessing effectiveness is reduced.

[0028] The through-holes can be formed as long, thin slits. In thiscase, it would be preferable, for the reasons described above, for thewidth of the slits to be at least 0.5 mm and no more than 3 mm.

[0029] It is possible to have a plurality of facing plates, eachequipped with a discharge opening. The plurality of facing plates can bearranged in a co-planar manner with gaps formed between adjacent facingplates. Advantages similar to those described above can be provided withthis structure. In this case, if the facing plates are all made the samesize (area), the substrate surface can be processed without unevenness.The sizes of the facing plates can be set to suit the requiredprocessing speed.

[0030] In the present invention, an appropriate space must be maintainedbetween the substrate and the facing plate, but the facing plate isheated by heat radiating from the heated substrate and the mounting baseso that thermal deformation can tend to take place. For this reason, ifa large substrate with a large area is to be processed, using asingle-piece facing plate can prevent an appropriate gap from beingmaintained with the substrate.

[0031] If the facing plates are formed from a suitable plurality ofplates, the thermal deformation in each of the facing plates can be keptvery small so that, as a result, the thermal deformation for the facingplates overall can be kept very small.

[0032] Substrates have been getting larger and larger in recent years,but with this structure, the surface of a large substrate can beprocessed uniformly even if the size exceeds 1100 mm×1300 mm.

[0033] Taking thermal deformation into account, it would be preferablefor the thickness of the facing plate to be at least 0.1 mm, and morepreferably at least 1 mm, in order to allow a good distance from thesubstrate to be maintained. Taking the time required to achieve thermalequilibrium in the facing plate, it would be preferable for thethickness to be no more than 5 mm, more preferably no more than 2 mm.

[0034] It is preferable for the space to be within the range of at least0.5 mm and no more than 3 mm. If the space exceeds 3 mm, unprocessedsections on the substrate surface corresponding to the gaps can remain.If the space is less than 0.5 mm, the exhaust efficiency of theprocessing gas is very poor and the processing effectiveness is reduced.

[0035] Examples of materials for the facing plate include fluorinatedresin, zirconia, mica, ceramic, stainless steel, silicon, aluminum,titanium, glass, and quartz. There are no restrictions on the shape,which can be triangular, rectangular, hexagonal, circular, andelliptical.

[0036] The mounting base, heating device, and facing plate can be placedin a processing chamber forming a closed space with the substrate beingprocessed in this processing chamber. In this case, the gasses in theprocessing chamber can be discharged outside by exhausting means. Bydischarging the gasses in the processing chamber, the exhaust of gassesfrom the through-holes and gaps can take place smoothly with noobstructions.

[0037] The pressure in the processing chamber exhausted by exhaustingmeans can be, in absolute pressure, at least 7 KPa. If the pressure inthe processing chamber is less than 7 KPa, the exhaust speed at whichgasses are discharged from the through-holes and the gaps becomes toofast, reducing the time during which the processing gas lingers betweenthe facing plate and the substrate and reducing the reaction efficiency.A more preferable pressure for the inside of the processing chamber isat least 14 KPa.

[0038] In terms of reaction efficiency, there are no restrictions to theupper limit of pressure inside the processing chamber, but in terms ofthe exhausting of product gas generated by the processing, it is bepreferable for the pressure inside the processing chamber to be no morethan the pressure (absolute pressure) of the processing gas supplysource.

[0039] With the present invention as described above, the facing platecontrols the thickness of the layer of processing gas flowing along thesubstrate surface, and the processing gas after the processing iscompleted (after reactions) is exhausted from the through-holes and thegaps between the facing plates. This makes it possible to uniformlyprocess the entire substrate surface while improving reaction efficiencyand processing efficiency for the processing gas.

[0040] The heating temperature of the substrate in the present inventioncan be in the range of 200°-500° C. Within this range, the processingdescribed above can be performed while at the same time impuritiescontained in the substrate can be vaporized. Also, the processing gascan contain at least 14% by weight of ozone. A mixed gas of ozone andTEOS (Tetraethyl orthosilicate, Si(C₂H₅O)₄) can also be used.

[0041] The above, and other objects, features and advantages of thepresent invention will become apparent from the following descriptionread in conjunction with the accompanying drawings, in which likereference numerals designate the same elements.

BRIEF DESCRIPTION OF THE DRAWINGS

[0042]FIG. 1 is a cross-section drawing showing the simplified structureof an ozone processing device according to an embodiment of the presentinvention, and is a cross-section drawing along the C-C line in FIG. 2.

[0043]FIG. 2 is a cross-section drawing along the A-A line in FIG. 1.

[0044]FIG. 3 is a cross-section drawing along the B-B line in FIG. 1.

[0045]FIG. 4 through FIG. 6 are bottom-view drawings showing facingplates from other embodiments of the present invention.

[0046]FIG. 7 is a cross-section drawing showing the simplified structureof an ozone processing device according to a conventional technology andis a cross-section drawing along the E-E line in FIG. 8.

[0047]FIG. 8 is a bottom-view drawing along the D-D line in FIG. 7.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0048] The present invention will be described in detail with referencesto the attached drawings.

[0049] As shown in FIG. 1 and FIG. 2, an ozone processing device 1according to this example is equipped with a processing chamber 10having a predetermined internal volume, a mounting base 20 disposed inthe processing chamber 10 and upon the upper surface thereof a substrateK is mounted, and a gas supply head 30 disposed above the mounting base20.

[0050] The processing chamber 10 is a case having a predetermined innervolume and closed by a cover 11. The processing chamber 10 is formed sothat gasses therein are discharged outside by an exhaust device 70 byway of exhaust pipes 71, 72, which are passed through and secured toside plates of the processing chamber 10. The exhaust device 70 adjuststhe internal pressure (absolute pressure) of the processing chamber 10so that it is at least 7 KPa (preferably at least 14 KPa) and no morethan the pressure of the ozone gas supply source.

[0051] The mounting base 20 is equipped with internal heating means (notshown) formed from a heater or the like. This heating means (not shown)heats the substrate K mounted on the upper surface. The mounting base 20can be raised and lowered by raising/lowering device 21. Thisraising/lowering device 21 is equipped with a raising/lowering rod 22that passes through the bottom surface of the processing chamber 10.This raising/lowering rod 22 supports the mounting base 20. Theraising/lowering rod 22 supports the mounting base 20. Raising/loweringdevice 21 is formed from, for example, a pneumatic cylinder, and anelectric cylinder.

[0052] Multiple support needles 23 formed with tapered ends areprojected from the bottom surface of the processing chamber 10, and thesubstrate K is loosely placed on the end surfaces. Support needles 23are inserted through through-holes (not shown) formed on the mountingbase 20 when the mounting base 20 is at its lowermost position, so thatthe ends project upward from the upper surface of the mounting base 20.When the mounting base 20 is at its uppermost position, the supportneedles 23 are pulled out from the through-holes (not shown).

[0053] The substrate K is loosely placed on the support needles 23 whenthe mounting base 20 is at its lowermost position. Then, the mountingbase 20 is raised and the support needles 23 move down relative to themounting base 20 so that the substrate K is mounted on the mounting base20.

[0054] The gas supply head 30 is formed from a block-shaped main headunit 31 and multiple facing plates 40 disposed at a predetermineddistance from the main head unit 31 and facing the substrate K on themounting base 20. The main head unit 31 is secured to the inner walls ofthe processing chamber 10 using securing members 12.

[0055] A cooling fluid flow path 32 passes through one side surface tothe other side surface of he main head unit 31. Cooling fluidcirculating device 50 shown in FIG. 2 supplies cooling fluid to thecooling fluid flow path 32, and this cooling fluid is circulated.

[0056] Cooling fluid circulating device 50 is formed from pipe fittings56, pipes 57, pipe fittings 58, pipes 59, cooling fluid supplying device51, a pipe 52, a pipe fitting 53, a pipe 54, and a pipe fitting 55, forexample. The pipe fittings 56 are connected to one end of the coolingfluid flow path 32, and the pipe fitting 55 is connected to the otherend of the cooling fluid flow path 32. The cooling fluid circulationpath is formed in this manner from the pipe fittings 56, the pipes 57,the pipe fittings 58, the pipes 59, cooling fluid supplying means 51,the pipe 52, the pipe fitting 53, the pipe 54, the pipe fitting 55, andthe cooling fluid flow path 32.

[0057] The cooling fluid 32 is supplied from cooling fluid supplyingdevice 51 to the cooling fluid flow path 32 by way of the pipe 52, thepipe fitting 53, the pipe 54, and the pipe fitting 55, in that order.After it passes through the cooling fluid flow path 32, the suppliedcooling fluid is circulated back to cooling fluid supplying device 51 byway of the pipe fittings 56, the pipes 57, the pipe fittings 58, and thepipe 59, in that order.

[0058] Ozone gas flow path 33 is formed in the main head unit 31openingto one of the side surfaces and gas conduction holes 34 opening to thelower surface and communicating with the ozone gas flow path 33. The gasconduction holes 34 are equipped with through-holes 36 that extend fromthe upper surface to the lower surface and are connected to gasconduction pipes 35 extended toward the substrate K.

[0059] Each facing plate 40 can be formed in a rectangular shape and isdisposed in a co-planar manner so that predetermined gaps 41 are formedbetween adjacent facing plates 40. The facing plates 40 are secured withbolts to support members 37, which are secured to the lower surface ofthe main head unit 31. If bolts are used for securing, counterbore holes42 are formed on the facing plates 40 to prevent the bolt heads fromprojecting from the lower surfaces of the facing plates 40. Examples ofmaterials preferable for the facing plates 40 include fluorinated resin,zirconia, mica, ceramic, stainless steel, silicon, aluminum, titanium,glass, and quartz.

[0060] Through-holes 43 passing from the upper surface to the lowersurface are formed on the facing plates 40, and the lower ends of thegas conduction pipes 35 are fitted to the through-holes 43. Lowersurface openings 43 a of the through-holes 43 serve, together with thelower openings 36 a of the gas conduction pipes 35, as dischargeopenings for discharging ozone gas. Ozone gas supplied from ozone gassupplying device 60 shown in FIG. 2 to the ozone gas flow path 33, thegas conduction holes 34, and the through-holes 36 are discharged fromthese discharge openings 43 a (36 a) to the substrate K.

[0061] Ozone gas supplying device 60 is formed from pipe fittings 65connected to the ozone gas flow path 33, pipes 64 connected to the pipefittings 65, pipe fittings 63 connected to the pipes 64, pipes 62connected to the pipe fittings 63, an ozone gas generating device 61connected to the pipes 62, and the like. Ozone gas (processing gas)having a predetermined concentration is supplied from the ozone gasgenerating device 61 to the ozone gas flow path 33 by way of the pipes62, the pipe fittings 63, the pipes 64, and the pipe fittings 65, inthat order.

[0062] In the ozone processing device 1 described above, the substrate Kis mounted on the support needles 23 using suitable means. At thispoint, the mounting base 20 is at its lowermost position. The coolingfluid is supplied by cooling fluid supplying device 51 and is circulatedthrough the cooling fluid circulation path 32 of the main head unit 31.The main head unit 31 is cooled by this cooling fluid.

[0063] Next, the pressure (absolute pressure) within the processingchamber 10 is adjusted by the exhaust device 70 to at least 7 KPa(preferably at least 14 KPa) and no more than the pressure of the gassupply source, and raising/lowering device 21 raises the mounting base20.

[0064] When the mounting base 20 is raised, the support needles 23 arelowered relative to the mounting base 20. The mounting plate K ismounted on the mounting base 20 and the mounting base 20 reaches itsuppermost position. Also, the substrate K mounted on the mounting base20 is heated by heating device (not shown).

[0065] Then, ozone gas with a predetermined concentration is suppliedfrom the ozone gas generating device 61 to the ozone gas flow path 33 ofthe main head unit 31 by way of the pipes 62, the pipe fittings 63, thepipes 64, and the pipe fittings 65, in that order. The gas passesthrough the gas conduction holes 34 and the through-holes 36 and isblown toward the substrate K from the discharge openings 43 a (36 a) ofthe facing plates 40.

[0066] The ozone gas discharged in this manner collides with thesubstrate K and forms a flow along it. In this flow, the ozone (O₃) isheated by the substrate K. This heating and the contact with thesubstrate K and the resist causes it to breaks down into oxygen (O₂) andactive oxygen (O*). This active oxygen (O*) forms an oxide film on thesurface of the substrate K or improves the oxide film on the surface ofthe substrate K or removes the resist film formed on the surface of thesubstrate K through a thermochemical reaction.

[0067] The ozone gas discharged from the discharge openings 43 a andflowing along the substrate K then collides with each other, forming aflow toward the gaps 41. The gas flows from the gaps 41 to the backsurfaces (upper surfaces) of the facing plates 41, i.e., is dischargedfrom between the substrate K and the facing plates 40. As a result, theozone gas which has completed its processing operation is prevented fromlingering around the surface of the substrate K to obstruct the flow ofozone gas discharged from the discharge openings 43 a (36 a) to thesurface of the substrate K. This allows the operations such as formingor improving oxide film or removing resist film to be performedeffectively.

[0068] The gaps 41 can be within the range of at least 0.5 mm and nomore than 3 mm. If the gap 41 is less than 0.5 mm, the exhaustefficiency of the ozone gas is very poor and the processing effect ofthe ozone gas is reduced. If the gap exceeds 3 mm, unprocessed sectionswill remain at areas corresponding to the gaps 41.

[0069] By discharging the gas in the processing chamber 10, thedischarging from the gaps 41 can be performed smoothly. In this process,it is preferable for the pressure (absolute pressure) in the processingchamber 10 to be at least 7 KPa (more preferably at least 14 KPa) and nomore than the pressure of the ozone gas supply source.

[0070] If the pressure in the processing chamber 10 is less than 7 KPa,the discharging from the gaps 41 becomes too fast, shortening the timeduring which the ozone gas can linger between the facing plates 40 andthe substrate K and reducing the effectiveness of the reaction. If thepressure within the processing chamber 10 exceeds the pressure of theozone gas supply source, the discharge of the product gas generated bythe processing does not take place smoothly.

[0071] The facing plates 40 serve to control the thickness of the ozonegas flow layer flowing along the surface of the substrate K. From thisperspective, it is preferable to have the facing plates 40 be as closeas possible to the substrate K. By doing this, the thickness of thelayer of ozone gas flow along the surface of the substrate K can be madethinner, allowing more ozone to contribute to the formation orimprovement of the oxide film or the removal of resist film, thusimproving the processing effectiveness.

[0072] Thus, the space between the substrate K and the facing plates 40must be maintained in an appropriate manner but the facing plates 40 areheated by radiated heat from the heated substrate K and the mountingbase 20, resulting in a tendency to thermally deform. As a result, whena substrate with a large area is to be processed, forming the facingplate 40 from a single plate may lead to thermal deformation thatprevents the distance from the substrate K to be maintainedappropriately.

[0073] In this example, the facing plates 40 are formed from multipleplates so that thermal deformation of each individual plate 40 can bekept very small. As a result, an effective distance from the substrate Kcan be used.

[0074] In recent years, substrates are becoming larger and larger, butwith this arrangement, surfaces can be processed uniformly even for alarge substrate K exceeding 1100 mm×1300 mm.

[0075] Taking thermal deformation into account, the thickness t for thefacing plates 40 that allows an effective distance from the substrate Kto be maintained is at least 0.1 mm, and more preferably at least 1 mm.Taking into account the time required for thermal equilibrium to beachieved in the facing plates 40, it would be preferable for thethickness t to be no more than 5 mm, more preferably no more than 2 mm.

[0076] If the facing plates 40 all have the same size (area), thesurface sections of the substrate K corresponding to the facing plates40 can be processed without unevenness. Also, the size of the facingplates 40 can be set to suit the required processing speed.

[0077] The atmospheric temperature within the processing chamber 10 isincreased by the heating performed by heating means (not shown). Themain head unit 31 is heated in this high-temperature atmosphere, butsince the main head unit 31 is cooled by the cooling fluid flowingthrough the cooling fluid flow path 32, the ozone gas flowing throughthe ozone gas flow path 33 is cooled by the cooling fluid and thetemperature thereof is kept within a fixed range. As a result, thethermal breakdown of ozone accompanying a rise in temperature isprevented and the lowering of the ozone concentration in the ozone gasis prevented.

[0078] The heating temperature of the substrate can be in the range200°-500° C. Within this range, the operations described above can beperformed while also vaporizing impurities contained in the substrate K.Also, the ozone gas can contain at least 14% by weight of ozone, or amixed gas of ozone and TEOS (Tetraethyl orthosilicate, Si(C₂H₅5O)₄).

[0079] With the ozone processing device 1 described in detail above, thethickness of the layer of ozone gas flowing along the surface of thesubstrate K is controlled by multiple facing plates 40 and the ozone gasthat has completed processing operations (reactions) is discharged fromthe gaps 41 between the facing plates 40. This improves the reactionefficiency and the processing efficiency of the ozone gas and allowsuniform processing of the entire surface even for a large substrate Kexceeding 1100 mm×1300 mm.

[0080] The above description presents an embodiment of the presentinvention, but the implementations of the present invention are notrestricted to this.

[0081] For example, the shape of the facing plates 40 is not restrictedto the rectangular shape described above. Besides the rectangular shape,it is possible to have gaps 77 formed so that the facing plates 75 withdischarge openings 76 are formed hexagonally. Alternatively, as shown inFIG. 5, gaps 82 can be formed so that the facing plates 80 withdischarge openings 81 are formed with triangular shapes. Also, facingplates with different shapes such as triangles and rectangles can becombined.

[0082] As shown in FIG. 6, an embodiment has multiple facing plates 40formed from a single facing plate 85, with slit-shaped through-holes 87formed on the facing plate 85 to partition the surface into multipleregions, each region being formed with a discharge opening 86.Advantages similar to those described above can be obtained with thisstructure. In this case, taking into account the discharge efficiency ofthe through-holes 87, it would be preferable for the slit width to be atleast 0.5 mm and no more than 3 mm.

[0083] The slit-shaped through-holes 87 can be replaced with multiplecircular holes that are lined up. In this case, the inner diameter ofeach circular hole can be at least 0.5 mm and no more than 3 mm.

[0084] As described above, the ozone processing device according to thepresent invention can be used effectively for forming oxide film on thesurface of a substrate, e.g., a semiconductor substrate or a liquidcrystal substrate, or improving oxide film formed on the substratesurface, or removing resist film formed on the substrate surface.

[0085] Having described preferred embodiments of the invention withreference to the accompanying drawings, it is to be understood that theinvention is not limited to those precise embodiments, and that variouschanges and modifications may be effected therein by one skilled in theart without departing from the scope or spirit of the invention asdefined in the appended claims.

What is claimed is:
 1. An ozone processing device for a substratecomprising: a mounting base upon which said substrate is mounted; aheating device heating said substrate on said mounting base; a facingplate disposed facing said substrate on said mounting base, comprising:plurality of discharge openings discharging a processing gas containingozone toward said substrate; and a through-hole disposed between saiddischarge openings and passing through a front and a back surfaces ofsaid facing place; and a gas supplying device supplying and dischargingsaid processing gas to said discharge openings of said facing plate. 2.An ozone processing device as described in claim 1 wherein: a pluralityof said through-holes partition said facing plate into a plurality ofregions; and said discharge openings are formed one in each regionpartitioned by said through-holes.
 3. An ozone processing device asdescribed in claim 2 wherein said through-hole has a hole diameter of atleast 0.5 mm and no more than 3 mm.
 4. An ozone processing device asdescribed in claim 1 wherein: said through-holes are formed as long,thin slits and said facing plate is partitioned by said through-holes;said discharge openings are formed one in each region partitioned bysaid through-holes.
 5. An ozone processing device as described in claim4 wherein the width of said slit is at least 0.5 mm and no more than 3mm.
 6. An ozone processing device as described in claim 1 wherein thethickness of said facing plate is at least 0.1 mm and no more than 5 mm.7. An ozone processing device as described in claim 1 wherein: at leastsaid mounting base, said heating device, and said facing plate aredisposed in a processing chamber forming a closed space; and adischarging device discharges gas in said processing chamber to saidprocessing chamber outside.
 8. An ozone processing device as describedin claim 7 wherein said discharging means adjusts pressure (absolutepressure) within said processing chamber to at least 7 KPa.
 9. An ozoneprocessing device as described in claim 7 wherein said discharging meansadjusts pressure (absolute pressure) within said processing chamber toat least 14 KPa.
 10. An ozone processing device for a substratecomprising: a mounting base upon which said substrate is mounted; aheating device heating said substrate on said mounting base; a pluralityof facing plates facing said substrate on said mounting base including aplurality of discharge openings discharging a processing gas containingozone toward said substrate; and a gas supplying device supplying anddischarging said processing gas to said discharge openings of saidfacing plate; wherein said plurality of facing plates are disposed in aco-planar manner so that gaps are formed between adjacent facing plates.11. An ozone processing device as described in claim 10 wherein saidgaps are at least 0.5 mm and no more than 3 mm.
 12. An ozone processingdevice as described in claim 10 wherein the thickness of said facingplate is at least 0.1 mm and no more than 5 mm.
 13. An ozone processingdevice as described in claim 10 wherein: at least said mounting base,said heating device, and said facing plate are disposed in a processingchamber forming a closed space; and a discharging device discharges gasin said processing chamber to outside said processing chamber.
 14. Anozone processing device as described in claim 13 wherein saiddischarging means adjusts pressure (absolute pressure) within saidprocessing chamber to at least 7 KPa.
 15. An ozone processing device asdescribed in claim 13 wherein said discharging means adjusts pressure(absolute pressure) within said processing chamber to at least 14 KPa.16. A device for processing a substrate with a processing gascomprising: a mounting base mounting said substrate, comprising: aheater heating said substrate; a plurality of facing plates disposedopposite said substrate; wherein each of said plurality of facing plateshaving a discharge opening discharging said processing gas toward saidsubstrate; and a gas supply device supplying said processing gas towardsaid discharge opening; wherein each said plurality of facing plates aredisposed spaced from the other said plurality of having plates forming aplurality of gas capturing gaps to collect said processing gas.